Tag: parthenogenesis

Questions Related to parthenogenesis

Whiptail lizard show

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Periodic parthenogenesis

  2. Paedogenic parthenogenesis

  3. Obligatory parthenogenesis

  4. Incomplete parthenogenesis

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Correct Option: C
Explanation:

Parthenogenesis is a natural form of asexual reproduction in which growth and development of embryo occur without fertilisation. The offspring arise from a single organism and inherits the genes of that parent only, it does not involve the fusion of gametes, and almost never changes the number of chromosomes.

There are mainly two types of parthenogenesis: facultative and obligatory. 
In facultative parthenogenesis, there is switching between sexual reproduction and parthenogenesis.
In obligatory parthenogenesis organisms exclusively reproduce through asexual means. Whiptail lizards are unisex reptiles which reproduce only asexually. A female will produce an ovum with a full set of genes provided solely by the mother. Thus, a male is not needed to provide sperm to fertilise the egg. This type of asexual reproduction is a serious threat to biodiversity due to lack of gene variation and decreased the fitness of offspring.
Incomplete or periodic parthenogenesis are same as facultative parthenogenesis where sexual reproduction alternates with parthenogenesis. For e.g., in bees and wasps, some eggs develop without fertilisation and produce females and those eggs that are fertilised develop into males.
Paedogenic parthenogenesis is found in Gallfly, where larva may lay eggs which develop parthenogenetically into the new generation of larvae.
Thus, the correct answer is option C.

Parthenogenesis is formation of

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Embryo without fertilization

  2. Embryo from pollen sac

  3. Sporophytic plantlet from gametophyte

  4. Fruit without fertilization

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Correct Option: A
Explanation:
Parthenogenesis is the development of an embryo from an unfertilised egg or if a spermatozoon does penetrate the egg, there is no union of male and female pronuclei. It is a mode of asexual reproduction. On the basis of division, it is of two types apomictic parthenogenesis and automictic parthenogenesis.
In apomictic parthenogenesis, the mature egg cells are produced by mitotic divisions, and these cells directly develop into embryos. The offsprings produced are full clones of the mother.
In automictic parthenogenesis, the mother cell undergoes meiosis and produces haploid offspring which are the half clone of the mother cell.
So, the correct answer is option A.

Parthenogenesis is the development of fruit

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. With viable seeds after fertilization

  2. With viable seeds after pollination

  3. With viable seeds without fertilisation

  4. Without seeds after pollination

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Correct Option: C
Explanation:

Parthenogenesis is a natural form of asexual reproduction in which growth and development of embryo occur without fertilisation. It can occur without meiosis  i.e., division to form haploid cells. Mature egg cells are formed by the mitotic division of ovary or somatic cells and these cells directly develop into embryos. In flowering plants, cells of gametophyte can undergo this process. The seeds thus formed are viable and produce exact replica or clone of their mother.

Thus, the correct answer is option C.

Thelytoky, a type of parthenogenesis, occurs in

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Aphids

  2. Typhlina

  3. Honey Bee

  4. Wasp

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Correct Option: A
Explanation:

The type of parthenogenesis in which females are produced from unfertilized eggs is known as thelytoky. The daughter cells produced are diploid in nature. It mainly occurs in aphids. It is mainly of two types, apomictic and automictic. 

So, the correct answer is option A.

Parthenogenesis is

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Formation of egg without fertilization

  2. Formation of synergids without fertilization

  3. Formation of fruit without fertilization

  4. Formation of fruit without pollination

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Correct Option: C

The term parthenogenesis was introduced by

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Charles Bonnet

  2. Karl von Baer

  3. Spallanzani

  4. None of the above

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Correct Option: A
Explanation:

Charles Bonnet was first to introduce the term parthenogenesis. He studied the process of parthenogenesis in aphids. He kept the female aphids unfertilized in isolation and observed the development of the viable embryo from the unfertilized female eggs. 

Parthenogenesis is the development of an embryo from an unfertilized egg or if a spermatozoa does penetrate the egg, there is no union of male and female pronuclei.
So, the correct answer is option A.

Development of seedless fruit in an unfertilized flower is called

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Parthenocarpy

  2. Sporophytic budding

  3. Polyembryony

  4. Micropropagation

Show answer
Correct Option: A
Explanation:

After pollination and fertilization, plants produce seed and fruits. The process of formation of fruit without fertilization is called as parthenocarpy.

So the correct option is 'Parthenocarpy'.

A dandelion produces seeds without meiosis or fertilisation. The adult sporophyte forms diploid, rather than haploid, megaspores that develop into ovules containing diploid, rather than haploid nuclei. One of the nuclei in each ovule becomes an egg and develops directly, without fertilisation, into an embryo that is genetically identical to its parent. This type of reproduction is called ____________________.

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Parthenogenesis, which is a form of apomixis

  2. Parthenogenesis, which is a form of amphimixis

  3. Adventive embryony, which is a form of apomixis

  4. Agamosphermy, which is a form of amphimixis

Show answer
Correct Option: A
Explanation:

Apomixis (Gk. apo-without, mixis-mixing) is a mode of reproduction which does not involve the formation of zygote through gametic fusion. Apomixis is thus asexual reproduction. Parthenogenesis (Gk. parthenos - virgin, genesis - produce) refers to the development of an egg/ovum into a complete individual without fertilisation.

Nuclear embryos found in citrus sp. Are.

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Parthenogenesis

  2. Aposporous

  3. Apogamous

  4. Adventives

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Correct Option: A

Lectin of pollen is involved in _____________.

zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

  1. Parthenogenesis

  2. Pollen sterility

  3. Pollen allergy

  4. Self-incompatibility

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Correct Option: A